8bitworkshop/presets/vcs/vcslib/rand8.ca65

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.include "vcs-ca65.inc"
.global _randseed8
.global _initrand8
.global _nextrand8
.global _prevrand8
_randseed8: .res 1
.proc _initrand8
lda INTIM
ora #1
sta _randseed8
rts
.endproc
.proc _nextrand8
lda _randseed8
lsr
bcc :+
eor #$d4
:
sta _randseed8
rts
.endproc
.proc _prevrand8
lda _randseed8
asl
bcc :+
eor #$a9
:
sta _randseed8
rts
.endproc